I've narrowed it down to five possibilities at present:
(a) KNIGHT CITY - a low-power, street-level supers game (set in Knight City, of course), inspired primarily by Alphas, but also Misfits and Heroes, with an early X-Men vibe to it. Basically a collection of 'mutants' ( e.g. 'ordinary' people with a single power) working for the government, or an organisation, tracking down other gifted people and thwarting superpowered crime.
I haven't decided on a system yet for this, as Icons isn't really geared for this kind of play and Mutants & Masterminds isn't simply too fiddly for my tastes (I don't want lists and lists of skills and feats to keep track of). I think I'd probably go for a modern era but non-supers system and just houserule the powers element, if the chosen system didn't already some equivalent.
(b) SPACE: 1889 - Who doesn't like Victorian steampunk, right? I think if I went this route it would be with the Ubiquity system, as I mentioned the other day, using a combo of Leagues Of Adventure and the German Space: 1889 rules.
(c) TUNNELS & TROLLS - A gonzo, full-on, Arduin-inspired, treasure-hunting, monster-slaying dose of madness. As simple as that.
I think part of my problem with previous attempts at running fantasy games was the sheer amount of barriers and walls I threw up, in an attempt to emulate a particular style of play (e.g. gritty swords and sorcery).
This way I'd let the style and tone of the campaign shape itself through play.
(d) MONSTER HUNTERS - For ages I've been kicking around the idea of a modern-day game of monster hunters using the Margaret Weis Productions Supernatural game (which, for me, is their best use of the Cortex System).
Perhaps it's time to put my money where my mouth is, man up and try something a little different. This would certainly be unlike any campaign we've played to date.
(e) CTHULHU IN SPACE - Cthonian Stars is a near-future sci-fi setting, operating under the Mongoose iteration of Traveller rules, but with a dark, Lovecraftian twist. Currently only available in PDF, I'm waiting for the print edition to become available.
My main concern with this setting - which also part of its appeal (as with most Lovecraftian RPGs) - is the potential fragility of the player-characters as an obstacle to long-term play.
I'm excited about all these settings, but ultimately want to settle on one that I'd be happy running for the foreseeable future (Gamer ADHD willing!)